1. Field of the Invention
The present invention generally relates to a pixel structure, a touch display panel and a liquid crystal display, in particular, to a fringe field switching pixel structure, a touch display panel and a liquid crystal display.
2. Description of Related Art
Recently, with the optoelectronic technology and the technology of manufacturing semiconductor maturing, the development of the flat panel display is vigorous promoted. The liquid crystal display gradually replaces the conventional cathode ray tube display based on the advantages of low operation voltage, non-radiation, light weight and small volume, and thus becomes the main stream of the recent display products. However, the liquid crystal display still has a problem of restricted viewing angle. At present, the technology for achieving wide viewing angle display effect includes a twisted nematic (TN) liquid crystal combined with a wide viewing film, an in-plane switching (IPS) liquid crystal display, a fringe field switching (FFS) liquid crystal display and a multi-domain vertically alignment (MVA) liquid crystal display. Herein, the conventional fringe field switching liquid crystal display is discussed.
The schematic top view diagram and the schematic cross-sectional diagram of a pixel structure according to a conventional fringe field switching liquid crystal display are shown in FIG. 1A and FIG. 1B. Referring to FIGS. 1A and 1B, a pixel structure 100 disposed on a substrate 10 includes at least a scan line 102, at least a data line 104, an active device 106, a first electrode 108 and a second electrode 110. The scan line 102 and the data line 104 demarcate a rectangular pixel region P. The first electrode 108 and the second electrode 110 are located in the rectangular pixel region P and the second electrode 110 is electrically connected to the active device 106. In addition, the second electrode 110 is disposed between the first electrode 108 and the substrate 10. The first electrode 108 has a plurality of slits 108A so as to expose a portion of the second electrode 110, that is to say, a portion of the conductive pattern of the first electrode 108 is not overlapped with the second electrode 110 at where the plurality of slits 108A is located.
It is noted that the first electrode 108 is not electrically connected to the active device 106, but electrically connected to a common voltage source (not shown). When the pixel structure 100 displays, the first electrode 108 and the second electrode 110 are applied by different voltages so as to generate a fringe field effect and render the liquid crystal display represent the wide viewing angle display effect.
The pixel structure 100 is apt to improve the display effect of liquid crystal display. However, certain undesirable effect may occur when the liquid crystal display having the pixel structure 100 attached with a touch panel to form a touch display panel. For example, the liquid crystal molecules of the liquid crystal display may be disturbed and thus disorderly arrange when a user press the above-mentioned touch display panel. Accordingly, the phenomenon of uneven brightness may occur at the place surrounding the touch point and the judgments of the touch input or the writing input of the touch panel may be harmfully influenced. In the meantime, the slits 108A of the pixel structure 100 are capable of having an influence on the restore time of the disturbed liquid crystal molecules. In particular, the longer the length of the slits 108A is the prolonging the restore time of the disturbed liquid crystal molecules is.